Talk:Climate sensitivity/Archive 1

Archive 1

Archive 2

I reviewed the allegedly independent observational contraints on climate sensitivity

All citations, including (surprisingly) Shaviv are to some extent based on models, with Shaviv explicitly relying upon Gregory for part of his work. Gregory explicitly relied upon models for his estimate of heat flux into the ocean for the late 19th century, and based other assumptions on model insights and results. Annan relied upon models to analyze the maunder minimum, and also mistakenly assumed the maunder was long enough to achieve equilibrium, which is contradicted by climate commitment studies, which estimate closer to 1000 years.--Poodleboy 07:25, 10 June 2006 (UTC)

AR4

According to the draft of the fourth IPCC, current models favor a climate sensitivity of about 3 degrees C, with a narrowing of the range from previous versions. See page 8-42: "As discussed in Chapter 10, the current generation of AOGCMs covers a range of equilibrium climate sensitivity from 2.1 to 4.4°C (with a mean value of 3.2°C, Table 8.8.1, Chapter 10, Box 10.2)". This page should be updated to reflect newer work, at least once the final draft of the IPCC is released. -- 207.71.226.132 19:00, 12 February 2007 (UTC)

Better to use the SPM, which is released. I've updated the page William M. Connolley 19:49, 12 February 2007 (UTC)

Baseline

It would be good if a little more information were given (possibly by links to other articles) about the changes which constitute a doubling of CO2. It is not clear from this article that temperature is related to CO2 logarithmically, or why it assumed to be so, and so it might (to people such as myself who would guess it was a linear relationship) raise questions of when and where the doubling is measured from (280ppm? 380ppm?). Also it could be clearer how N20, CH4 etc are included in the single CO2 parameter. Thanks if anyone can add this. --87.112.15.72 12:36, 19 August 2007 (UTC)

The article doesn't talk about the T-CO2 log relation, nor is it clear that it should do. Baseline: everyone thinks of 280 but I'm not sure this is necessary William M. Connolley 14:46, 19 August 2007 (UTC)

I agree that the logarithmic depndence of forcing on CO2 concentration needs justification. It is interesting to consider the cooling that would result if the log. relationship held true for reduction of CO2 as well as increases. The earth's tmperature would drop to absolute zero, before the CO2 conc. reached zero. --Phwitz (talk) 18:45, 23 June 2008 (UTC)

Schwartz

I removed Schwartz [1]. It too new, and almost undoubtedly wrong [2] William M. Connolley 10:22, 31 August 2007 (UTC)

I protest against POV deletion of peer reviewed literature Hans Erren (talk) 22:31, 5 December 2007 (UTC)

If you can't see the obvious errors then you have shown yourself to be incompetent to comment. If you can see the errors and want to include it regardless, then you are dishonest.Jdannan (talk) 22:52, 5 December 2007 (UTC)

Jdannan, please reread Wikipedia:Assume good faith. Also see Climate Insensitivity and AR(1) Models . The issue doesn't appear to be as clear-cut as you suppose. Pete Tillman (talk) 21:11, 26 December 2007 (UTC)

I'm not assuming anything, merely pointing out two possible conclusions, which appear to be exhaustive to me. I don't find any support for Schwartz's analysis in the link you provided. Regardless, it is but one minor paper which is hardly representative of scientific opinion. Jdannan (talk) 04:19, 27 December 2007 (UTC)

I had contributed the following para:

Schwartz (2007) advanced a new method of calculating Earth's climate sensitivity based on a whole-Earth energy balance model. According to this model the climate sensitivity can be determined empirically as the time constant characterizing fluctuations in global mean surface temperature (determined from autocorrelation of the time series of that quantity) divided by the effective heat capacity of the climate system (determined from time series of ocean heat content and global mean surface temperature). Based on a suggestion by Scafetta (2008), Schwartz (2008) revised his estimate of climate sensitivity to 0.51 ± 0.26 K/(W m^-2), corresponding to an equilibrium temperature increase for doubled CO₂ of 1.9 ± 1.0 °C. This approach is considered quite controversial (Knutti et al. (2008), Foster et al. (2008)).

Jdannan deleted it stating (One irrelevant wrong paper doesn't merit such lengthy discussion)

I invite further discussion of the matter

Steve1941 (talk) 22:52, 6 November 2008 (UTC)

Schwarz is indeed wrong, and minor. Are you under the impression that his paper is of some merit? William M. Connolley (talk) 23:05, 6 November 2008 (UTC)

William, the suggested insertion cites a paper published in a premier, refereed, learned-society journal; the suggested insertion also calls attention to and cites published criticism of the paper in a neutral way. It seems inappropriate for a user to deny such an entry based on his assertion that the paper is "wrong, and minor." Steve1941 (talk) 05:56, 9 November 2008 (UTC)

Sample calculation using industrial-age data

The last sentence of this sub section currently reads "(All numbers are approximate and somewhat uncertain.)"

I had changed this to replace "somewhat" by "quite" and add "This uncertainty limits present ability to meaningfully estimate climate sensitivity by such a calculation."

Kim D. Petersen reverted this. We discussed this on his/her talk page [3] but I am moving the discussion over here. He/she wrote "The trouble i had with that text was the apparent original research, in the change. And that it seems to emphasise the uncertainty beyond whats necessary." --Kim D. Petersen (talk) 22:08, 5 November 2008 (UTC)

I wrote "I would say that the total forcing over the industrial period of 1.6 W m-2 (range, 0.6 - 2.4, 2 sigma) given in AR4, SPF fig 2; see also page 131) is quite uncertain, not somewhat uncertain. I refer you also to gregory et al's paper in j climate 2002. So what is your gripe about my change? Would you be happier if I stated the uncertainty range and gave a citation?"

I would like to broaden the discussion so I have moved it over here. I invite further discussion. It seems like several people are actively reading this page.

Steve1941 (talk) 22:39, 6 November 2008 (UTC)

Issue with the essentials

It is improper to consider radiation from greenhouse gases equivalent to solar radiation, relative to forcing. Solar radiation and changes to albedo are forcing the incident energy and affect the energy balance. Radiation from greenhouse absorption and clouds doesn't affect the energy balance, but affects the temperature profile in the atmosphere.

It is also inconsistent to include the effects of feedback here, while the IPCC definition of radiative forcing specifically says it excludes feedback.

The Stefan-Boltzmann law effect from doubling CO2 is only 0.7K. When greenhouse gas absorption under clouds is ignored, the effect is reduced to 1.3 W/m^2, resulting in less than a 0.25K increase in average surface temperature. The only positive feedback effect that can have enough effect is the ebb and flow of surface ice and an increase of 0.25K isn't going to melt a lot of ice. We are also relatively close to minimum ice anyway, so any positive feedback from melting ice will disappear. This is the nature of a non linear feedback term and is generally not accounted for in climate models. Minimum ice doesn't mean no ice, since ice is unavoidable at the poles, which are dark for half the year and at higher altitudes which are much colder in winter. Water will undermine the N pole in summer to mostly melt it at minimum ice, but the S pole ice is over land and will not melt away until continental drift moves Antarctica into more northern latitudes.

This asymmetry in the ebb and flow of ice provides amplification effects, relative to when perihelion occurs. We see this today in the satellite data where the Sun is closer in January and the average global temperature should be about 3C warmer than it is in July when the Sun is farthest away. Instead, the global average temperature in Jan is 4C colder. This is because of the N hemisphere snow pack reflects energy away while in the S hemisphere, most snow falls on water and doesn't accumulate. The satellite data confirms this from measurements of surface reflectance. This illustrates the dynamic range if ice and snow relative to reflecting energy. If the snow pack was glacial ice instead, this 7C reduction in temperature caused by increased reflection would be persistent. The satellite data can be found here: http://isccp.giss.nasa.gov. The most appropriate raw data to use is the d2data set. George2wiki (talk) 20:23, 16 April 2009 (UTC)

Issue with gross inaccuracies and political bias in a scientific article

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The fact that this quantification of climate sensitivity is being used to justify a multi-trillion experiment in climate modification is grossly irresponsible. The fact that corrections to the text have been removed because those corrections undermine the validity of CO2 forcing is even more irresponsible as it perpetuates the hand waving arguments used to support anthropomorphic forcing.

Rounding up the Stefan-Boltzmann law warming by 40% (0.7 vs. 1.0 C) and then claiming that the feedback effects are 3-4x bigger than this is ludicrous. There is absolutely no evidence of any CO2 related feedback except that attributed to biology, which is a negative feedback. More warmth -> more biomass -> more energy extracted to construct biomass. You can not bundle in feedback from ice and clouds and call it CO2 feedback. You can not violate Conservation of Energy because it helps your explanation. You can not extrapolate short term behavior from changes in long term averages. You can not extrapolate climate sensitivity at the limits (ice age, interglacial) from the transition between them. Please, go understand the basics of nonlinear feedback systems. You can not use linear equations to approximate a relationship were power density (forcing) is proportional to temperature raised to the forth power.

What ever happened to peer review? How could any of this junk science being promoted gain any kind of legitimacy?

George2wiki (talk) 15:56, 17 April 2009 (UTC)

I'm sorry but wikipedia is not a forum for general discussions or a soapbox to tell what you/we believe. We go firmly by what the reliable sources tells us. And Ramstorf(2008) as well as the IPCC TAR (which Ramstorf(2008) cites) are such reliable sources (as well as peer-reviewd) - your assertions aren't. (btw. you just calculated the black-body sensitivity - correct? Earth is a gray-body (it has albedo)). And contrary to what you tell us here, the literature tells us that the Earth has positive feedbacks, and that you can calculate climate sensitivity this way. --Kim D. Petersen (talk) 16:23, 17 April 2009 (UTC)

No, you can't do a simple minded 'open loop' calculation like this. Feedback systems are closed loop. The feedback is non linear. The relationship between energy and temperature is non linear. There are many other factors involved. There are multiple feedback loops in the system. Oversimplifying will only lead to incorrect conclusions, as the IPCC has demonstrated. Regarding BB radiation, the albedo doesn't enter in when you want to calculate how much power density is associated with a specific surface temperature. In this case, 288K. You can use Stefan-Boltzmann to calculate exactly how much extra energy is required to increase the temperature by 1K resulting in a calculated sensitivity of about .18. Albedo affects the energy balance. Greenhouse gases don't, except water vapor by the action of clouds. Lumping in all feedbacks as it they were caused by CO2 is incorrect because what you are really doing is saying what is the sensitivity of the climate to temperature change, in this case, the tiny fraction of a degree K that doubling CO2 will have. Moreover, the IPCC definition of radiative forcing excludes feedback effects. Claiming a climate sensitity to change which is 3-4 times bigger than it actual is will cause models to break, i,e. diverge (runaway warming) or just produce unreasonable results. Relative to reliable source, first principles are the most reliable. George2wiki (talk) 15:08, 18 April 2009 (UTC)

If you're really interested in learning about climate feedbacks, I suggest reading Understanding Climate Change Feedbacks (2004). National Research Council. Panel on Climate Change Feedbacks, Climate Research Committee. National Academies Press. ISBN 0309090725. -Atmoz (talk) 16:48, 17 April 2009 (UTC)

I have read through these and they are so full of assumptions and omissions that they can not be relied on. Just because something is published doesn't make it correct. And BTW, the IPCC is not a scientific organization, but a political one. It's unfortunate that subjectivity is allowed in politics and we have let it carry over into science, which must be objective. —Preceding unsigned comment added by George2wiki (talk • contribs)

You haven't read it. If you had, you wouldn't have confused it with the IPCC. -Atmoz (talk) 18:47, 18 April 2009 (UTC)

You're wrong, but that doesn't really matter. The point at issue is we report what the science says William M. Connolley (talk) 18:15, 18 April 2009 (U

The science means the data and the physics. Start with first principles and explain the data. The problem here is to really understand how the climate works, you need a working knowledge of thermodynamics, quantum mechanics, biology, atmospheric physics, orbital mechanics, black body radiation, data reduction, nonlinear feedback control systems, frequency domain analysis, and statistical analysis. Few have any of these skills and far fewer have all, which makes it very easy to pass off speculative claims as truth, especially when such claims bolster other agendas and are supported by fear. If you want to see an objective analysis of the data which is driven by first principles, look here: http://www.palisad.com/co2/slides/siframes.html. —Preceding unsigned comment added by George2wiki (talk • contribs) 23:26, 18 April 2009 (UTC)

Sorry, but what you are saying is original research(follow the link please) and is ruled out by WP policy. And the linked site is not a reliable source(again follow link), so it cannot be used here. (and can hardly be called "objective" (from a quick glance at the commentary ("the alarmists"...)) --Kim D. Petersen (talk) 23:40, 18 April 2009 (

According to this poster, Wikipedia articles on global warming have been systematically biased: http://rate.forbes.com/comments/CommentServlet?op=cpage&sourcename=story&StoryURI=2009/12/29/climate-change-hurricane-al-gore-opinions-contributors-michael-fumento.html] My addition and it's reversal is another example. --118.208.128.236 (talk) 23:01, 31 December 2009 (UTC)

You (in the sense of that IP) haven't made any edits. Which one do you mean? William M. Connolley (talk) 23:19, 31 December 2009 (UTC)

Sorry - forgot to sign in. Yes Connolley applying the "unreliable source" rule in a rather dictatorial manner.--Blouis79 (talk) 23:37, 31 December 2009 (UTC)

Are you really arguing for inclusion of [4]? I thought it was obvious why it is unacceptable. I can tell you why if you don't know William M. Connolley (talk) 10:08, 1 January 2010 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Issue with violating Conservation of Energy

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Use the talk page to discuss the editing of the article with reference to verifiable facts from reliable sources. Extensive discussions of basic science may be conducted on more suitable websites.

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Energy re-radiated from greenhouse gas absorption is really solar energy that arrived at an earlier time. The models cited by the references that I've reviewed so far, count atmospheric re-radiation the same as incident solar energy and end up double counting this energy, relative to it's forcing effect. It's crucial to understand that relative to the energy balance, the action of greenhouse gas absorption and subsequent re-emission is not to add new energy to the system, or to trap old energy forever, but just to add additional delay between when energy arrives and ultimately leaves the planet. George2wiki (talk) 08:07, 21 April 2009 (UTC)

I'm sorry - but this is once more original research. Find some reliable sources that state your objection specifically with the subject domain in mind, if you want to continue this further. --Kim D. Petersen (talk) 08:30, 21 April 2009 (UTC)

This has nothing to do with original research. Conservation of energy is a well known physical law. I will be happy to give up my objection if a peer reviewed reference than explains how greenhouse gases create new energy out of nothing is included. All of the other references cited seem to assume that this is the case. George2wiki (talk) 16:31, 21 April 2009 (UTC)

Sorry - but find a reliable source that states this connection directly: Ie. radiative forcing is wrong and violates conservation of energy, or that the references are getting their science wrong. Until then you will never get further, since those are the rules that WP works under. Your assertions (which in WP terminology is original research) are irrelevant. --Kim D. Petersen (talk) 16:36, 21 April 2009 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Issue with an unjustified assumption

The article and all of the references assume that greenhouse gases force the climate. The ultimate references for this assumption seems to be an initial ice core analysis which shows the link between CO2, CH4 and the average temperature and hypothesizes that it's greenhouse forcing at work. Subsequent analysis has shown that CO2 is indicative of prior temperature change and not predictive of future change. The Dome C ice core record further confirms this.George2wiki (talk) 08:07, 21 April 2009 (UTC)

And since that is what the references say, that is what wikipedia says. Btw. noone disagrees that GHG's are a feedback over glacial/interglacial transitions. Please stop arguing about how wrong the references are - and instead provide references that back up your arguments. --Kim D. Petersen (talk) 08:49, 21 April 2009 (UTC)

A reference that contradicts CO2 forcing is:

Hubertus Fischer, Martin Wahlen, Jesse Smith, Derek Mastroianni, Ice Core Records of Atmospheric CO2 Around the Last Three Glacial Terminations Science 12 March 1999: Vol. 283. no. 5408, pp. 1712 - 1714 [5] I have independently verified their findings and applied the same verification analysis to the more recent Dome C ice core data which again confirms that CO2 concentration changes are indicative of past temperature change and not predictive of future change and combined with CH4 relationships can be explained as the ebb and flow of biomass as an ecosystem adapts to temperature changes. George2wiki (talk) 21:58, 21 April 2009 (UTC)

I don't know what you are trying to convince us about here (or why you pick such an old paper). As stated above - no one disagrees that CO2/CH4 are feedbacks over glacial/interglacial transitions, and i mean absolutely no one. (and the paper does not contradict CO2 forcing (in fact it mentions it as a given)). --Kim D. Petersen (talk) 23:08, 21 April 2009 (UTC)

Actually, James Hansen disagrees (2007 paper). I tried to add this info last October, but it was immediately removed as "original research" even though I quoted directly from Dr. Hansen's paper. Q Science (talk) 03:40, 22 April 2009 (UTC)

What you were talking about there is something complete different. I've just reread the paper, and Hansen is rather specific in stating that there is/must be a lag between forcing (insolation changes) and response (GHG,temp). To be even more specific: Hansen is talking about forcing => temp (fast in relative terms), and discrepansies in that, whereas the GHG changes are slow responses, and uses this (amongst other factors) to show that CO2 will remain in the atmosphere for a long time after emissions cease. --Kim D. Petersen (talk) 13:52, 22 April 2009 (UTC)

I can say the same about the age of the references used by all the papers which claim greenhouse gas forcing is predominate. This idea was first floated when the ice core data arrived, but before anyone thought to perform a cross correlation analysis of change to change between greenhouse gases and temperature. All of these references date back to the same time and all of the newer references rely on these older references to establish greenhouse forcing as a predominate climate driver. Even an alarmist (David Roper) [6] noticed that CO2 lagged temperature and that CH4 lags by even more, although he tries to hand wave it away with a mutual feedback argument. I've also duplicated his correlation analysis as part of a more comprehensive set of correlation metrics, and have applied it to multiple ice core data sets. And while no one disagrees that changes in GHG concentrations has an effect on surface temperature, what is at dispute is the magnitude of this effect and the veracity of the methodology established by the IPCC to justify heuristic coefficients for an effect far larger than what we observe and to roll in future effects far larger than known physics can support. Regarding the slow response of GHG changes, any temperature influence caused by a GHG concentration change is almost immediate and relative to change, will not even be observable in the ice core data. The same is true for changes in CO2 solubility of the oceans, as a function of temperature. All influences of these effects, including any forward CO2 related feedback, are for all intents and purposes, coincident with temperature changes relative to the temporal resolution of the ice cores. The ice core data shows a significant component of CO2 (and CH4) change occurs centuries after the temperature change and shows significant hysteresis. As is pointed out in the paper, biology is the most likely cause as the Earth's ecosystem adapts to climate change. If the Earth's basic thermodynamic system responded as slow as it needs to in order for the data to be consistent with the idea that greenhouse gas forcing predominates, there would be no seasonal change, lakes would never freeze and sea ice would never form. The only long term feedback that can be seen in the ice cores is the ebb and flow of surface ice and snow. This is nonlinear positive feedback, whose effect drops to zero at minimum/maximum ice.George2wiki (talk) 20:02, 22 April 2009 (UTC)

Sorry - but out of 25 references used in the article - exactly 1 is as old or older than yours... So you cannot say that. And "any temperature influence caused by a GHG concentration change is almost immediate and relative to change" is incorrect, the reason that its not even close to immediate is that the Oceans have to warm (and cool) to a new equilibrium state. The rest of your posting is the usual jumble of original research that you post here.

There are in the article a total of 13 scientific references in (amongst others) Journal of Geophysical Research, Science and Nature - that directly contradict your assertions about feedbacks and climate sensitivity. While you haven't brought even a single reliable source to the table.... --Kim D. Petersen (talk) 20:45, 22 April 2009 (UTC)

The climate sensitivity for the whole atmosphere

The climate senstitvity (without water-vapour feedback) equates to (((1368/4*0.7+1)/5.67e-8)^0.25-273.15) - (((1368/4*0.7)/5.67e-8)^0.25-273.15) = 0.27 K/(W/m2). The average column integrated water vapour is 30 kg/m2 [7]. The heat of vaporization is 2.27MJ/kg [8] and the relative water vapour increase is 0.06 /K [9]. The product equates to 4.1 MJ/m2/K. The global average precipitation is about 1m/year [10] [11] i.e. 1000kg/m2/y. The average residence time of water molecules in the troposphere is about (30kg/m2)/(1000kg/m2/y) = 0.03y = 11 days =9.5e5 s [12]. Thus evaporation takes (4.1 MJ/m2/K)/(9.5e5 s) = 4.3 W/m2/K, i.e. 0.23 K/(W/m2). This can be also checked that the temperature encrease 0.22K/10years [13] corresponds to the average column integrated water vapour increase 0.22K/10y * 0.06/K * 30kg/m2 = 0.4kg/m2/10year close to the reported value 0.41 [14]. The climate senstivitivy for the whole atmosphere is close to the senstivity from irradiation without any (chemical) feedback. And more. The average near-surface temperature (without the greehouse effect) for the average albedo from space 0.296 [15] is -18°C [16] (the surface albedo is about 0.2 [17]). This is close to the current (density weighted [18]) average column temperature below -20°C (or -17°C for [19]). The near-surface temperature is increased (the vaporization - the sensitivity could be increased) by about 35°C to 15°C and the "tropopause" temperature is decreased (the cloud formations - the sensitivity is shifted to negative values [20]) down to -74°C (decrease by a similar heat flux 150W/m2 - now present in the near-surface atmosphere) as it is mentioned here [21]. Thus our clouds ("vapourhouse") are the true inversion (the more cooled air goes up due to the greenhouse effect) and the "inversion" [22] is normal (the ground fog). The heat from incoming radiation is only redistributed (conserved). —Preceding unsigned comment added by 86.49.12.197 (talk) 16:38, 9 September 2009 (UTC)

Reference format

This article uses a variety of reference formats. I think they should be changed so they're consistent. Anyone have a preference? -Atmoz (talk) 05:58, 11 September 2009 (UTC)

Cloud and Radiation Budget Changes Associated with Tropical Intraseasonal Oscillations

Please could someone add a reference to the following paper.

Spencer, Braswell, Christy & Hino, 2007: Cloud and Radiation Budget Changes Associated with Tropical Intraseasonal Oscillations, Geophysical Research Letters. August 9. [23]

The paper shows recent evidence from NASA's Aqua satellite showing that the net thermal feedback of cloud systems in the tropics is strongly negative.

Note: I have removed earlier text related to this subject for reasons discussed here: [24] Reissgo (talk) 10:01, 21 September 2009 (UTC)

Per earlier talk: that paper isn't obviously about climate sensitivity. Could you point to some bits of it that you think are relevant here? William M. Connolley (talk) 10:38, 21 September 2009 (UTC)

In Discussion and Conclusions it says "Our measured sensitivity of total (SW + LW) cloud radiative forcing to tropospheric temperature is -6.1 ..." Reissgo (talk) 10:49, 21 September 2009 (UTC)

Thats not climate sensitivity, at least not directly. What connection are you (or they?) making? William M. Connolley (talk) 11:27, 21 September 2009 (UTC)

The gist is that many people assumed that hot periods caused a lack of clouds which in turn cause more heat i.e. positive feedback or high sensitivity. He presents evidence, from satellite data that the cause and effect are the other way round, i.e. lack of clouds causes heating which then causes more clouds causing cooling, i.e. negative feedback, low sensitivity. Reissgo (talk) 11:56, 21 September 2009 (UTC)

I don't think I understand this. (a) is hot+ => cloud- => hot+. (b) is cloud- => hot+ => cloud+. You can't get from a to by by changing the causation - ie where you start in the loop. YOu have to change the sign of the feedback: hot+ has to cause cloud+ not cloud-. Are you sure that your "the cause and effect are the other way round" is right? William M. Connolley (talk) 15:50, 21 September 2009 (UTC)

Errm, and are you sure about "causes more clouds causing cooling"? I'm seeing "longwave flux anomalies unexpectedly transitioned from warming to cooling, behavior which was traced to a decrease in ice cloud coverage." Could you be clearer about exactly which bit you're interpreting? William M. Connolley (talk) 15:54, 21 September 2009 (UTC)

Belt and braces: just in case I made a mistake in paraphrasing his work here, I'd like to add that an additional reason to believe that this paper is about climate sensitivity is that Dr Spencer gave a talk entitled "Recent Evidence for Reduced Climate Sensitivity" [25] which was very largely (50%?) about this paper. Reissgo (talk) 12:44, 21 September 2009 (UTC)

Um, that was the bit that was deleted as a false start? The youtube video isn't usable for *anything*, especially not for interpreting the meaning of a paper. If it isn't clear from the paper itself, it can't be said. WP:SYN etc William M. Connolley (talk) 15:50, 21 September 2009 (UTC)

It seems inappropriate for me (an amateur) to be arguing whether or not these papers have anything to do with climate sensitivity when the main author (a multi-award winning senior climate scientist) of the (published) papers himself says they are about climate sensitivity. Ok, I concede that lectures on video may not be appropriate for the main page, but surely they are admissible for establishing this tertiary issue on the talk page, no?

Here's a quote form the paper, "This indicates that the net (SW + LW) radiative effect of clouds during the evolution of the composite ISO is to cool the ocean-atmosphere system during its tropospheric warm phase, and to warm it during its cool phase."

Here's another quote, "The decrease in ice cloud coverage is conceptually consistent with the ‘infrared iris’ hypothesized by Lindzen et al. [2001], who proposed that tropical cirroform cloud coverage might open and close, like the iris of an eye, in response to anomalously warm or cool conditions, providing a negative radiative feedback on temperature change." Reissgo (talk) 13:31, 22 September 2009 (UTC)

I could reply here, but I'm waiting for some answer to my questions above William M. Connolley (talk) 13:50, 22 September 2009 (UTC)

I feel that the two quotes trump my other answers and establish that the paper is about climate sensitivity on their own, particularly the line "providing a negative radiative feedback on temperature change". Therefor it is currently of no consequence what my response is to the other "thread". Reissgo (talk) 14:21, 22 September 2009 (UTC)

You refuse to answer, so I'll have to do it for you: your precis which I questionned shows that you failed to understand the paper William M. Connolley (talk) 18:56, 22 September 2009 (UTC)

Let us say for arguments sake that I am not clever enough to be able to win the argument based on our other "thread", but if the quotes I have given clearly show, to anyone who cares to read them, that the paper is concerned with climate sensitivity, is that not in and of itself good enough reason to consider this work for inclusion on the main page, or just as a reference on the main page? Which part of "providing a negative radiative feedback on temperature change" is not concerned with climate sensitivity? Reissgo (talk) 20:48, 22 September 2009 (UTC)

Interestingly enough, i've read the quotes... And it certainly isn't clear to me how measurements of changes during ISO (intraseasonal oscillation), is indicative of more than inter seasonal changes, nor does the conclusion of the paper strengthen that clarity. A short time scale of less than a season cannot be extrapolated into the long timescales of climate (decades) - and the paper also makes that clear. Climate sensitivity is for climate time scales. --Kim D. Petersen (talk) 15:37, 23 September 2009 (UTC)

The paper says "not necessarily indicative" but then quickly goes on to say "...their behavior should be considered when testing the convective and cloud parameterizations in climate models that are used to predict global warming." So he's saying that the effect he has measured should be considered when trying to estimate climate sensitivity. Additionally this paper [26] perfectly illustrates how ignoring a short term (day-to-day) fluctuation can lead to errors in long term prediction. Reissgo (talk) 09:02, 24 September 2009 (UTC)

• Why don't you put this over at Cloud feedback (which could use some help) & maybe summarize at Cloud#Clouds_and_climate. IB there are some other recent pubs on this topic as well. Cheers, Pete Tillman (talk) 19:51, 22 September 2009 (UTC)

I am not familiar enough with the wikipedia philosophy to make that decision. Reissgo (talk) 20:48, 22 September 2009 (UTC)

Be bold. It will likely be reverted or massively altered as cloud feedbacks are not well understood and the conclusions of Spencer et al. represent only one view so adding just that paper would give it undue weight. A better solution would be to try and accurately summarize the state of the science; review articles are a good way of doing this. See this paper by Stephens. -Atmoz (talk) 05:30, 23 September 2009 (UTC)

Thank you for a well considered response, I was beginning to feel like I was taking part in the monty python "argument clinic" sketch [27]! I have a few questions in response: I note that the example paper you gave was submitted in summer 2003 which means that it presumably it was discussing papers several years older than that, approximately how long does a paper have to have been published before it is considered worthy of referencing/discussion on the main page? If the answer is "it depends" then I'd like to know what it depends on. Couldn't the reference be prefaced with a phrase like "recent results suggest..." or similar? Another question is, if say 95% of published papers are giving results broadly in line with, shall we say "the consensus" and 5% give results which are "non consensus", shouldn't the main page reflect that? BTW, I'm not taking about 95:5 with respect to popular opinion, or political commentators etc, I'm talking about peer reviewed papers in serious journals. I've just made up the 95% figure, I'd be interested to hear your estimate of the true ratio. Reissgo (talk) 09:11, 23 September 2009 (UTC)

Another place to start would be the IPCC Fourth Assessment Report, which might be a bit more up-to-date. My recollection is of a chart that shows the CF effect so poorly known, that they weren't even sure of the sign! It's a very interesting, and very poorly-understood, topic. For that matter, so is climate sensitivity.... <G>

As Atmoz hinted, writing climate-change stuff here is not for the faint of heart. If you do, please try to make your additions as even-handed and WP:NPOV as possible. If you're new to Wikipedia, you may want to start with something less fraught. Have fun, Pete Tillman (talk) 16:58, 23 September 2009 (UTC)

While I would claim to be enough of a scientist to be able to tell that this was good quality work and related to climate sensitivity, I do not claim to be a climate specialist and able to write a suitable wikipedia entry here. My motivation for bringing up this paper in the first place was my curiosity to see what the "mainstream" would say in response. Now that this section has had a collection of civilized responses from a variety of people who are not saying "you fool, this paper is completely inappropriate" it is clear that this paper is worthy of serious consideration. Maybe this talk section should simply be left for a while in order to allow a good number of people to read the paper in detail. Reissgo (talk) 17:28, 23 September 2009 (UTC)

You've now struck your previous argument. This is a step forward, because it indicates that you are abandoning it. It would be nice to know whether you are doing so because you now consider it to be erroneous, or because you now realise you don't understand the paper well enough to attempt to precis it William M. Connolley (talk) 10:59, 24 September 2009 (UTC)

That's now irrelevant. If you want to discuss this point, do so on my talk page. Reissgo (talk) 12:08, 24 September 2009 (UTC)

No, the relevance is, do you have a clue what is going on? Surely you must at least know *why* you struck your argument? William M. Connolley (talk) 12:50, 24 September 2009 (UTC)

I refuse to continue our personal flame on this page. Reissgo (talk) 13:43, 24 September 2009 (UTC)

Potential Biases in Feedback Diagnosis from Observational Data: A simple Model Demonstration

Please could someone add a reference to the following paper.

Spencer, R. W., and W. D. Braswell (2008), Potential biases in feedback diagnosis from observational data: A simple model demonstration, J. Clim., 21, 5624– 5628 [28]

Neatly demonstrates how an error in the assumption that daily cloud cover percentages was essentially random noise and so could be modelled by assuming a constant value, would directly and inevitably lead to a misdiagnosis of positive feedback. Reissgo (talk) 09:02, 21 September 2009 (UTC)

Wrong place -- see comment in section above, re Cloud feedback . Cheers, Pete Tillman (talk) 20:28, 22 September 2009 (UTC)

Maybe I'm being ignorant, but I thought that cloud feedback was an integral and major part of climate feedback. I also thought that climate sensitivity was proportional to the inverse of the climate feedback. Putting these two statements together leads to: cloud feedback being an integral and major component of climate sensitivity. is that not the case? Reissgo (talk) 11:55, 23 September 2009 (UTC)

Article probation

Please note that, by a decision of the Wikipedia community, this article and others relating to climate change (broadly construed) has been placed under article probation. Editors making disruptive edits may be blocked temporarily from editing the encyclopedia, or subject to other administrative remedies, according to standards that may be higher than elsewhere on Wikipedia. Please see Wikipedia:General sanctions/Climate change probation for full information and to review the decision. -- ChrisO (talk) 02:42, 2 January 2010 (UTC)

Richard Lindzen link

The Richard Lindzen page has a section called climate sensitivity and linking to this page as the main article. The page there describes Lindzen's Iris hypothesis along with an incomplete record of the pro/contra evidence (the iris hypothesis page has more recent data). Should this page add Lindzen's Iris hypothesis to the "other estimates" section or would it be better to link Lindzen's page to the Iris hypothesis page? Or perhaps both should be done. The status quo of linking Lindzen to here without talking about Lindzen (or did I gloss over that part of the article?) or his theory on this page doesn't make much sense to me. How should we resolve the inconsistency? TMLutas (talk) 06:17, 29 March 2010 (UTC)

The Iris hypothesis page looks about right - it is a bit too kind to the idea, but no-one really cares. The stuff on Lindzen's page is less coherent, rather like L's ideas, so should probably be tidied up (ditto). This page mentions neither, which seems about right: no-one really believed it at the time, and certainly no-one belives it now William M. Connolley (talk) 14:37, 29 March 2010 (UTC)

Please stop baiting. Other than the tone, I've no problem with your suggestion to break the link to this page and will pick things up on Lindzen's page. TMLutas (talk) 18:51, 29 March 2010 (UTC)

Rm Idso: why

I took the Idso stuff [29] out. The tag was broken, but more importantly the paper is obsolete. This isn't the history-of-CS page William M. Connolley (talk) 11:42, 27 July 2010 (UTC)

What is your definition of "obsolete"? It cannot be the publication date [e.g. Einstein's original paper on relativity is still valid], and regarding the paper content you should refer to a scientific review about the paper to justify your decision to remove it. Many references cited in the section "Other estimates" are questionable regarding the quality of the scientific content, but I wouldn't consider any as "obsolete" because they are all directly related to the topic and not proven wrong anywhere. If you have scientific arguments that could convince me that the approach used by Idso is wrong please let me know. By-the-way I do not know what a "sock" is. Bertrand Maroon (talk) 03:32, 5 August 2010 (UTC)

Climate sensitivity is a rapidly evolving field - or at least it was from ~1990 to about-now. Early papers from that period are likely to be of only historical interest. And the Idso one was junk. But I see I was wrong, in that *is* the historical section, so I guess Idso can stay, little though I like it. But it is 1998, not 2001 William M. Connolley (talk) 08:04, 5 August 2010 (UTC)

Thank you. Bertrand Maroon (talk) 12:16, 5 August 2010 (UTC)

This is a rubbish article in need of a complete rework

I came to this article to find the sensitivity of the climate to a change in solar radiation. Instead I read an article that seems to be solely about CO2 global warming with the merest glance towards the actual subject of climate sensitivity.

OK, CO2 can be a section in the article, but to have something like 90% of the article on CO2 is absurd, particularly when it so extensively covered and repeated in almost every other climate article.

And worst of all it doesn't actually give the basic direct climate sensitivity without all the hypothetical feedbacks. All I want is a straightforward figure for how much direct radiation leads to surface heating and I really could do without all the added rubbish - or at least have the subject split into direct and indirect effects so I could get the bit I need out of it. 85.211.148.163 (talk) 17:39, 23 March 2011 (UTC)

To give you an example of how pathetic this article is: the first sentence says: "Climate sensitivity is a measure of how responsive the temperature of the climate system is to a change in the radiative forcing." Therefore all measures of climate sensitivity should be in K/(W/m2) so what kind of numbskull would then talk about sensitivity in K. Either the definition is completely up the creek or the article which repeatedly talks about sensitivity in C is up the creek. Come one this isn't good enough! 85.211.148.163 (talk) 17:44, 23 March 2011 (UTC)

• You are correct that the climatological concept of Climate Sensitivity is rather a muddle, but that's what they use, so that's what an encyclopedia article must report. Hopefully the science of this will be sorted out some day, but it's not an easy problem, and not helped by the politicization of climatology. HTH, Pete Tillman (talk) 20:50, 23 March 2011 (UTC)

Radiative forcing due to doubled CO2

This section of the article badly misrepresents the cited sources, and probably goes into more detail than makes sense.--IanOfNorwich (talk) 08:31, 18 August 2011 (UTC)

Please add the details of the simple calculation of 1 deg response mentioned---or add a reference to somewhere in Wikipedia it is done. — Preceding unsigned comment added by G. Blaine (talk • contribs) 21:38, 22 September 2012 (UTC)

Rahmstorf should have clarified his claim that "Without any feedbacks, a doubling of CO2 (which amounts to a forcing of 3.7 W/m2) would result in 1 °C global warming, which is easy to calculate" in two respects: (a) given the forcing of 3.7 W/m2 one can infer 1 °C of warming (b) provided the ratio T/E of temperature T to net radiative flux E, suitably averaged over 24 hours and the globe, is about 1.08 K/(W/m2).

With that additional information the Stefan-Boltzmann formula in differential form, dE/dT = 4E/T, gives ΔT = (T/E)×(ΔE/4) = 1.08×(3.7/4) = 1 K. Reasonable values for T and E that give T/E = 1.08 would be T = 283 K and E = 262 W/m2.

This easy application of Stefan-Boltzmann naively assumes that T and E are measured and vary at a given altitude, typically either the surface or the tropopause. That the entire column from surface to top of atmosphere (TOA) radiates and varies widely in temperature over that range of altitudes shows that the Planck feedback defined in this naive way does not accurately reflect physical reality, even before consideration of other feedbacks. If there's an easy way of improving the accuracy by taking this into account I'd love to know about it. Vaughan Pratt (talk) 23:07, 14 December 2013 (UTC)

Schmittner

There is no reason to single out Schmittner to go in to the lede. It is merely the most recent paper on the subject, no more.

It belongs in the "recent dev" section, but only in context. Out of context, as it was, it badly biases that section, so I've removed it for now William M. Connolley (talk) 17:54, 22 December 2011 (UTC)

Schmittner was not being singled out for inclusion in the lead, Knutti and Hegerl are already there and in fact that is the only place they are mentioned at all. I note that you have left them untouched. Do you think this appropriate?

Regarding whether Schmittner is lead worthy it seems logical that the latest available estimates should be included there so as not to mislead the reader. The IPCC estimates are now outdated by more recent developments. Note that the IPCC estimates were left as well to provide a full picture to the reader. Failing to note the more recent development is misleading.

You also indicate that Schmittner was being taken out of context. Please explain what context was missing so that it can be included. Thanks. --Hypoxic mentalist (talk) 18:18, 22 December 2011 (UTC)

Schmittner was added, quite deliberately, because it is a lower-than-average estimate. Hence, the intent to mislead. Asserting that the IPCC estimates are outdated is rtue, but only subtly so, and needs careful handling. In particular the estimate of the most likely value is not outdated. It is not true that the most recent estimate should be automatically included in the lede. A virtue of K+H is that it is several years old William M. Connolley (talk) 18:32, 22 December 2011 (UTC)

I fear you read too much into my motives. I merely want to have the latest available data included in the article in a way that does not mislead the reader. Note that when I say outdated it is not the same as saying superceded. Clearly the IPCC estimate has more weight than a single paper but we must not present outdated information as if later developments do not exist. Can we agree on that point? K+H was added to the lead to supplement the IPCC values with more up to date findings. Arguing that they should be left there because they are several years old and I assume because they findings tend to reinforce that IPCC view is clearly biased. As follow on works both K+H and S should be treated comparably. There is no justification for treating them differently that I can see, nor is there any justification for keeping the most recent information out of the lead assuming we wish to present an up to date view of the science here.

How do you suggest that we address these issues, or are you arguing that S should be left out of the article enetirely? --Hypoxic mentalist (talk) 19:00, 22 December 2011 (UTC)

Schmittner was added, quite deliberately, because it is a lower-than-average estimate - I meant, into the text lower down, not your addition to the lede. Sorry if that was ambiguous. and I assume because they findings tend to reinforce that IPCC view - no; because they reflect the general view of subsequent research. Which is what we want from the lede. K+H should not be treated equally; we don't just stuff papers in at random, allocating them all the same weight, with no judgement. keeping the most recent information out of the lead assuming we wish to present an up to date view of the science here - you are mistaking the most recent paper for the most up to date view; this is the "each paper overturns all that has gone before" view, and is false. That paper is, as I said at the start, just one paper that happens to be the most recent. It should not get any extra weight for being the most recent. Indeed, since it is so recent that there has been no time for any comment in the literature, it should be de-weighted, quite heavily.

are you arguing that S should be left out of the article entirely? - no, as "It belongs in the "recent dev" section... so I've removed it for now" should have told you: it belongs in the article. In context. How do you suggest that we address these issues - firstly, we could wait for others to comment. Secondly, we could provide the proper context. It is on my to-do list for the festive fun period William M. Connolley (talk) 19:08, 22 December 2011 (UTC)

Very good. We seem to be agreed that S should be included and you seem to be on board with suggesting an appropriate manner of inclusion in relatively short order (I assume to be measured in days rather than weeks or months) so I am fine waiting to hear what you have to offer. Do bear in mind as you consider the matter that the lead should summarize the entire content of the article, including new developments. Cheers. --Hypoxic mentalist (talk) 19:22, 22 December 2011 (UTC)

While I modified the wording rather than remove the mention from the lead, as I've noted on my talk page one of the co-authors says in an interview, "we haven’t disproven the IPCC or high climate sensitivities. At least, not yet. This comes down to what generalizations can be made from a single, limited study. This is why the IPCC bases its conclusions on a synthesis of many studies, not relying on any particular one." So we must be careful not to give the misleading impression that it overturns the previous IPCC synthesis, or is even necessarily very significant. RC provides some useful links and pointers. . dave souza, talk 23:51, 22 December 2011 (UTC)

Agreed. As I noted above this single study does not supercede the IPCC, but it is more recent information worth noting. --Hypoxic mentalist (talk) 02:06, 30 December 2011 (UTC)

Structure

The current structure is odd. The "history" section does Charney, then leaps on to 2008. I have a feeling that it has been re-organised, and "subsequent" really refers to "subsequent to IPCC AR4" William M. Connolley (talk) 19:18, 9 January 2012 (UTC)

Experimental estimates of CS section outdated?

I'm pretty sure there are some recent peer-reviewed papers on this that aren't mentioned -- ones that give lower estimates than IPCC AR4, ims.

One source, with some interesting comments, is Chip Knappenberger at [30] -- this is for the peer-reviewed estimates he cites, not his commentary. I don't have time now to review this now, but will later.... --Pete Tillman (talk) 18:04, 6 April 2012 (UTC)

WMC: could you please comment on Ira Glickstein's analysis of Scmittner 2011 here? I don't know quite what to make of his multi-modal comments. Is this your field? Maybe I should try Andy Dessler?

I'm also thinking of adding this graphic, IPCC IPCC AR4 Figure 9.20, to the article. I think we can use IPCC charts as Fair Use? Note that one could interpret this graphic as suggesting multi-modality? Thanks, Pete Tillman (talk) 22:11, 8 April 2012 (UTC)

Nothing at WUWT is worth a second's attention on wikipedia,*unless* you have some independent reason for thinking so William M. Connolley (talk) 07:23, 9 April 2012 (UTC)

---

Here are the other recent CS estimate papers that Knappenberger mentions;

• N. P. Gillett et al. 2012, Improved constraints on 21st-century warming derived using 160 years of temperature observations: Geophysical Research Letters, Vol. 39, No. 1.

"Our analysis also leads to a relatively low and tightly-constrained estimate of Transient Climate Response of 1.3–1.8°C, and relatively low projections of 21st-century warming… which is towards the lower end of the observationally constrained range assessed by [the IPCC AR4]."

• Lauren Padilla et al. 2011, “Probabilistic estimated of transient climate sensitivity subject to uncertainty in forcing and natural variability”: J. Climate, 24, 5521–5537.

"For uncertainty assumptions best supported by global surface temperature data up to the present time, this paper finds a most likely present-day estimate of the transient climate sensitivity to be 1.6 K, with 90% confidence the response will fall between 1.3 and 2.6K…"

• Magne Aldrin et al., 2012, “Bayesian estimation of climate sensitivity based on a simple climate model fitted to observations of hemispheric temperatures and global ocean heat content,” : Environmetrics Volume 23, Issue 3, pages 253–27. (obviously not an experimental estimate!)

"The [climate sensitivity] mean is 2.0°C… which is lower than the IPCC estimate from the IPCC Fourth Assessment Report (IPCC, 2007), but this estimate increases if an extra forcing component is added, see the following text. The 95% credible interval (CI) ranges from 1.1°C to 4.3°C, whereas the 90% CI ranges from 1.2°C to 3.5°C."

• Roman Olson et al., 2012, “A climate sensitivity estimate using Bayesian fusion of instrumental observations and an Earth Systems model,”  : JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 117, D04103, 11 PP.

"Current climate model projections are uncertain. This uncertainty is partly driven by the uncertainty in key model parameters such as climate sensitivity (CS)…The mode of [our] climate sensitivity estimate is 2.8°C, with the corresponding 95% credible interval ranging from 1.8 to 4.9°C."

I'm also looking for more graphics, to make this article more comprehensible to an average, non-tech reader! -- Pete Tillman (talk) 22:38, 8 April 2012 (UTC)

When you posted the first one, i did a google scholar check on climate sensitivity papers - and there are 100+ gscholarhits[31]. Are you attempting to do original research to figure out what the average is, or where the papers are leading? (just as Knappenberg did)? If so - then please open a blog somewhere.... Wikipedia doesn't do original research. --Kim D. Petersen (talk) 23:38, 8 April 2012 (UTC)

No OR, these are all new(ish) peer-reviewed estimates of CS, which is (as you may recall) a long-standing interest of mine. Posted here so we can discuss which to include. WIP. Best, Pete Tillman (talk) 00:51, 9 April 2012 (UTC)

Actually the 100+ papers that i linked to, are all new(ish) papers... What is your selection criteria? And "long-standing interest" is WP:OR, posting it here doesn't change that. Without a proposal for some non-original selection criteria, that in some way reflects the weight in the literature - it is - simply original research. --Kim D. Petersen (talk) 01:30, 9 April 2012 (UTC)

Climate sensitivity in the AR5 SOD

Judith Curry has an interesting and thought-provoking post on this at Climate etc.. Premature for this article, and tangled up in IPCC (etc) politics: but it does appear to me that the better recent empirical estimates of ECS are coming in substantially below previous IPCC estimates -- and below the current draft of the upcoming AR5. She is apparently planning a publication on "what I think is wrong with climate model simulations of water vapor feedback." Worthwhile reading this material, and Nic Lewis's careful (but informal) work. To my eye, the best current empirical estimate of ECS is around 1.5 deg. C/doubling. Note that this is a "heads-up" post, just FYI, not for current addition to the article. But I'm unhappy with the lead (and only!) graphic being a modelling study. Will return to this, --Pete Tillman (talk) 20:49, 19 December 2012 (UTC)

Yes, Lewis & Curry (Climate Dynamics, September 2014) have authored a peer-reviewed paper based upon AR5 data which shows that median estimate of climate sensitivity (ECS) is a paltry 1.64 degree for a doubling of CO2.

Now we see why AR5 declined to state a median best estimate, like they did in AR4, while lowering the bottom range to 1.0.

Expect this study to be banned from this article by the Hockey Team. — Preceding unsigned comment added by 71.160.162.50 (talk) 17:31, 26 September 2014 (UTC)

Slowdown in temperature rise

FB added, and I removed,

Some observers have noticed an unexplained reduction or even a flattening in temperature rise in the 21st century causing temperature rise at the lowest range of predictive models. This has occurred despite rapid increase in carbon dioxide. The uncertain role of clouds is suspected as a cause. If the observed pattern continues climate sensitivity would be projected to be 2° C or less.<ref name="A sensitive matter">{{cite news|title=A sensitive matter|url=http://www.economist.com/news/science-and-technology/21574461-climate-may-be-heating-up-less-response-greenhouse-gas-emissions|accessdate=March 30, 2013|newspaper=The Economist|date=March 30, 2013}}</ref>

I don't like adding stuff that is so new. "Some observers" is weaselly. And I really don't like using the Economist as sole source for science. "The uncertain role of clouds is suspected as a cause" isn't really right, that's a paraphrase of a paraphrase and too much has been removed. "If the observed pattern continues..." fails WP:CRYSTAL. Having said that, I quite like the Economist article [32]. We should probably include something about a possible lowering of CS, but using better sources more accurately William M. Connolley (talk) 18:34, 30 March 2013 (UTC)

I expected trouble from you... Good that you see the article has value though. The first time I heard about this I thought it was a hoax. User:Fred Bauder Talk 18:45, 30 March 2013 (UTC)

I think "The upper end of climate model temperature projections is inconsistent with past warming" covers some of this material. User:Fred Bauder Talk 18:52, 30 March 2013 (UTC)

As to WP:CRYSTAL "the uncertainties in future warming rates are expected to decrease, an expectation borne out by subsequent projections that also include 21st century observations." User:Fred Bauder Talk 19:04, 30 March 2013 (UTC)

"Observed 21st century temperatures further constrain likely rates of future warming" User:Fred Bauder Talk 19:18, 30 March 2013 (UTC)

"Observed climate change constrains the likelihood of extreme future global warming" User:Fred Bauder Talk 19:23, 30 March 2013 (UTC)

Your second link is broken. What did you intend? The third is from 2008, so unsurprisingly doesn't say anything about recent results. I think you've completely misread it, and misunderstood what it means by "constrains": as it says, The many uncertainties in aerosol physics and chemistry mean that a large range of present-day aerosol cooling is possible which could imply a large climate sensitivity, extremely large future warming and the increased risk of catastrophic consequences which is hardly supportive of the text I removed. Your first link is potentially more interesting, but doesn't directly speak to climate sensitivity William M. Connolley (talk) 20:08, 30 March 2013 (UTC)

Fixed the link. Aerosols seem to cool now, reduction, anticipated as pollution is reduced, would lesson that cooling. Good thing you and I will never have to live through this... User:Fred Bauder Talk 20:17, 30 March 2013 (UTC)

Thanks. I can only read the anstract, and the relevant bit appears to be "The highest rates of warming previously consistent with past warming now appear to be unlikely." Its not possible to translate that into any kind of numerical constraint on CS. Is the full text more helpful? William M. Connolley (talk) 20:26, 30 March 2013 (UTC)

All I can read too, keep looking at the references at the bottom of http://iopscience.iop.org/1748-9326/8/1/014024/pdf/1748-9326_8_1_014024.pdf User:Fred Bauder Talk 22:08, 30 March 2013 (UTC)

"After the middle part of the 21st century aerosol pollution is reduced rapidly under these scenarios and the warming therefore accelerates as the masking effect of aerosols is removed, revealing the consequences of a high transient climate response to increased greenhouse gas forcing." User:Fred Bauder Talk 01:23, 31 March 2013 (UTC)

(od) What about these?

• Sulfur stalls surface temperature rise; Findings explain decade without warming July 30th, 2011; Vol.180 #3 (p. 17) Science News
• Small volcanoes add up to cooler climate; Airborne particles help explain why temperatures rose less last decade August 13th, 2011; Vol.180 #4 (p. 5) Science News

108.195.137.95 (talk) 02:46, 31 March 2013 (UTC)

That IP is a known blocked editor. His contributions might be legitimate, but they should be ignored unless a real editor wants to take credit for it. — Arthur Rubin (talk) 09:43, 1 April 2013 (UTC)

R.K. Kaufmann et al. Reconciling anthropogenic climate change with observed temperature 1998-2008. Proceedings of the National Academy of Sciences. doi: 10.1073/pnas.1102467108 http://www.pnas.org/content/108/29/11790.full

http://www.sciencemag.org/content/328/5976/316.full http://www.sciencemag.org/content/328/5976/316/F1.expansion.html User:Fred Bauder Talk 04:18, 31 March 2013 (UTC)

Errm, hold on. We started off (or at least the Economist did) with the idea that recent obs tend to suggest a lower value for CS. That's a rather different thing to sulphates-have-caused-less-warming-recently which (if you believed it) would leave the value of CS untouched. Are we talking about the original stuff, or moving on to a more general discussion? William M. Connolley (talk) 10:47, 31 March 2013 (UTC)

We're just following out what the literature says. The literature seems to say that all the coal burning in China results in aerosols that mask the effect of the constantly increasing carbon dioxide resulting in little or no global warming during the last decade. This information, however, may not belong in this article as climate sensitivity itself should be a constant, not something based on empirical data heavily influenced by emissions resulting from pollution. User:Fred Bauder Talk 11:26, 31 March 2013 (UTC)

OK, so what about the figure we use at the top of this article? Its sourced to [33] but the text there doesn't really clarify what's plotted. Comparing to [34] I think what we have is from Stainforth, D. A., Aina, T., Christensen, C., Collins, M., Faull, N., Frame, D. J., Kettleborough, J. A., et al. (2005). Uncertainty in predictions of the climate response to rising levels of greenhouse gases. That's rather old now (8 years) and perhaps should be updated William M. Connolley (talk) 10:13, 1 April 2013 (UTC)

"Climate sensitivity is a measure of how responsive the temperature of the climate system is to a change in the radiative forcing" Radiative forcing includes both greenhouse gases and aerosols. The effect of the gasses considered by themselves is known, but that of various aerosols and their amount is not. It seems additional unknown factors such as the role of methane clathrate are also included. Given the role political and economic choices play reliable values seem difficult to come by, particularly as the situation develops. To return to the initial Economist article, 10, or 15, years of flat data seems to be rather short. User:Fred Bauder Talk 13:59, 1 April 2013 (UTC)

http://www.guardian.co.uk/environment/2013/mar/27/climate-change-model-global-warming User:Fred Bauder Talk 17:54, 1 April 2013 (UTC)

Baseline?

Apologies if this is an absurd question, but when we say "the temperature change in °C associated with a doubling of the concentration of carbon dioxide in Earth's atmosphere", what do we mean? Is the sensitivity thought to be constant, so that, whatever concentration of carbon dioxide you start with, you can say doubling this will give this much warming? Or is there some baseline that these discussions are measuring (e.g. carbon dioxide concentration in 1990)? N p holmes (talk) 11:58, 18 May 2013 (UTC)

It is not an absurd question,but there are some implicit (and reasonable ) assumptions in there. For a start, there are reasons to believe that the change in radiative forcing grows with the log of the level of CO₂, so it makes sense to talk about growth of CO₂ as a ratio (e.g. doubling) rather than some other measure. This assumption can be developed from physical principles, but it has also been verified experimentally. While there are limits to how many doublings can occur and still hold true, within the range of plausible CO₂ levels, it holds close enough for government work.--SPhilbrick(Talk) 14:39, 3 June 2013 (UTC)

FWIW, Rahmstorf (footnote 8) on page 37 argues that technically speaking, the doubling refers specifically to a doubling from 280 to 560. The results will be similar for other doubling (200 to 400 or 300 to 600), but not necessarily far outside that range. I think, but I am not certain, that as one goes up, the absorption bands will reach saturation and thus the forcing should grow slower, but that is not relevant to any ranges we are likely to see in our lifetimes.--SPhilbrick(Talk) 16:01, 3 June 2013 (UTC)

Uninformed readers like me will possibly be thinking of the range 400 to 800 (i. e. starting at present concentrations) when they start reading. At one point in the article, I now see, there is a mention of sorts. That's in the little paragraph in the middle of the section on IPCC4, which switches to a summary of the same from the EPA, in which a concentration of 540ppm (double preindustrial with a different value to the one Rahmstorf uses) is specified. But that's too late, buried in the article (and in a paragraph, which really should be put in the format of the rest of the article, so that a reader can rely on the IPCC alone and not a paraphrase of it). If someone were to put a brief summary of the Rahmstorf explanation, referenced to him, that would cover it. Something like "Calculations of sensitivity are generally made against pre-industrial levels (280ppm), but the same calculations can be expected to give the same sensitivity for other starting points." I didn't quite follow what Rahmsdorf was talking about with "initial states", if things like "how much heat the ocean can take up" are excluded. N p holmes (talk) 13:09, 4 June 2013 (UTC)

Edit needed

The following sentence appears to be nonsense, but it isn't immediately obvious how to fix it.

An estimate of the equilibrium climate sensitivity may be made from combining the effective climate sensitivity with the known properties of the ocean reservoirs and the surface heat fluxes; this is the effective climate sensitivity.

With added emphasis:

An estimate of the (X) equilibrium climate sensitivity may be made from combining the (Y) effective climate sensitivity with the (Z) known properties of the ocean reservoirs and the surface heat fluxes; this is the (Y) effective climate sensitivity.

Effectively, it says X is the combination of Y and Z; this is Y.--SPhilbrick(Talk) 14:44, 3 June 2013 (UTC)

Here are the related definitions from IPCC http://www.ipcc.ch/ipccreports/tar/wg1/345.htm Though basically today climatologist use the Earth system sensitivity which accounts for all known feedbacks.

The Earth system sensitivity including fast feedbacks from changes in water vapour, natural aerosols, clouds and sea ice, slower surface albedo feedbacks from changes in continental ice sheets and vegetation, and climate–GHG feedbacks from changes in natural (land and ocean) carbon sinks. Traditionally, only fast feedbacks have been considered (with the other feedbacks either ignored or treated as forcing), which has led to estimates of the climate sensitivity for doubled CO2 concentrations of about 3◦ C. The 2×CO2 Earth system sensitivity is higher than this, being ∼4–6◦ C if the ice sheet/vegetation albedo feedback is included in addition to the fast feedbacks, and higher still if climate–GHG feedbacks are also included. http://onlinelibrary.wiley.com/doi/10.1002/qj.2165/pdf

Prokaryotes (talk) 21:24, 21 September 2013 (UTC)

re: Sphilbrick: I agree that the sentence does not appear to make much sense. The sentence appears to be based on two sources - [35] [36]. These sources are cited in the sentence immediately following the one you have commented on. I suggest that the sentence is revised to more closely reflect these sources. In the meantime, a "clarification needed" tag could be added to the sentence. Enescot (talk) 09:27, 24 September 2013 (UTC)

Earth system sensitivity

You (P) appear to be confusing ESS with ECS. Its certainly not true to say that "basically today climatologist use the Earth system sensitivity". Its truer to say this is something that Hansen is pushing William M. Connolley (talk) 07:52, 22 September 2013 (UTC)

The ESS is based on NAS funding and work by AGU and used by the leading scientist on the field and in the relevant literature. Hansen is one of many authors. Can you point out where i confuse ESS with ECS? Prokaryotes (talk) 12:21, 22 September 2013 (UTC)

Example of leading Scientist using ESS today http://people.earth.yale.edu/earth-system-climate-sensitivity or http://www.nature.com/ngeo/journal/v3/n1/abs/ngeo706.html Prokaryotes (talk) 13:01, 22 September 2013 (UTC)

You've confused ECS with ESS up above. Your assertion "basically today climatologist use the Earth system sensitivity" is false. If yuo're trying to convince me that you don't know what you're talking about, you're doing well William M. Connolley (talk) 08:01, 23 September 2013 (UTC)

We could make a distinction between IPCC estimates and prevailing ESS models, but could you refer to the content not the talk page when we discuss the content? You previously removed the part on ESS and you removed my updated version of the Sensitivity to solar forcing which does not state the study conclusion, includes parts which are not referenced and is weasel worded, and beside that it is discussed earlier in the article. So i'm not sure how you plan to improve the article. Prokaryotes (talk) 08:32, 23 September 2013 (UTC)

I plan to improve the article by resisting changes that make it worse. There will also be a number of upgrades to put in once the IPCC AR5 comes out. As to what to discuss: if you confuse ESS and ECS on the talk page, then I need to discuss the talk page. That's not your only error, of course. As I said before, "basically today climatologist use the Earth system sensitivity" is false. Any arguments you've made that depend on it fail. If you've said nothing that depends on it, why say it? William M. Connolley (talk) 18:49, 23 September 2013 (UTC)

First of all you made 3 reverts on this without addressing your reason for it at all. Secondly, current part on ESS is misleading.

A less commonly used concept, the Earth system sensitivity (ESS), can be defined which includes the effects of slower feedbacks, such as the albedo change from melting the large ice sheets that covered much of the northern hemisphere during the last glacial maximum. These extra feedbacks make the ESS larger than the ECS — possibly twice as large — but also mean that it may well not apply to current conditions.

It is misleading to just focus on slow feedbacks or the conclusion that doubled sensitivity does not apply to current conditions! The resource does not say this! It is wrong to state "A less commonly used concept". I've provided above links to studies from today's leading climatologist which prefer to use ESS. Your reverts are to a version of ESS based on a blog from 2008. However, even the blog stated at the time:

The reason why the Earth System sensitivity might be more appropriate is because that determines the eventual consequences of any particular CO2 stabilization scenario

Your edits are disruptive, address your changes on the talk page before you revert.

The updated version:

The Earth system sensitivity (ESS), includes most known climate feedbacks. Included fast feedbacks are water vapour, natural aerosols, clouds and sea ice, slow feedbacks are ice sheets and vegetation, and GHG feedbacks from changes in natural (land and ocean) carbon sinks. In the past climate sensitivity was only considered based on the fast feedbacks (with other feedbacks either ignored or treated as forcing). The 2×CO2 Earth system sensitivity is ∼4–6◦ C when accounted for the ice sheet and vegetation albedofeedback, and higher still if climate–GHG feedbacks are included.

References

Sensitivity to solar forcing

Confusion between 2/3 and 3/2. Let's ignore all this and restart

Recently William M. Connolley (talk) removed [37] and he notes in his revert = v. please point out any "gross errors" in the solar part on talk. The gross error is = ..they estimate the equilibrium response to forcing would be about 1.5 times higher. when the cited study states = This excessive heat into the oceans tends to reduce the transient climate response for the atmosphere, but does not affect the modeled equilibrium climate sensitivity and The equilibrium climate sensitivity (ECS) should be greater than TCR, by approximately a factor of 3/2 The rest of this section is very poorly written, see WP:Jargon. Prokaryotes (talk) 09:21, 23 September 2013 (UTC) Sorry, I'm not understanding you. Why is 1.5 incompatible with 3/2? William M. Connolley (talk) 18:43, 23 September 2013 (UTC) This section is about solar forcing. The study is for most about the existence of the solar-cycle signal and finds a confidence level above 95%. The part reads However, they note that this is the transient response to a forcing with an 11 year cycle; due to lag effects, they estimate the equilibrium response to forcing would be about 1.5 times higher. This has nothing to do with the solar signal, i tried to make this more clear with adding the solar constant and mentioning the solar cycle for once in that section! Prokaryotes (talk) 22:29, 23 September 2013 (UTC) Further is it a gross error to state This would correspond to a transient climate sensitivity to carbon dioxide doubling of 2.5 to 3.6 K, There is no such thing as TCS. The proper term here is Transient climate response TCR, however that part is not related to the solar forcing in general (it relates to ocean heat uptake and related underestimation in specific model simulations) and it is not fully referenced! The article should be separated into ECS(Based on "Charney" often used for paleo estimates "without slow feedbacks of the Earth system", also different interpretation, i.e. use of feedback as forcing), ESS (Most complete based on earth system, is used to include more feedbacks, hence considered in the field to yield more reliable estimates - which are above Charney) and TCR (given time, few decades to i.e. calculate solar forcing or short term climate) Prokaryotes (talk) 01:20, 24 September 2013 (UTC) Can you make up your mind what is supposed to be wrong, please? When you said 1.5 times higher (your bold) I assumed that was your problem. Now you say its something else. Which is it? William M. Connolley (talk) 17:24, 24 September 2013 (UTC) Both, 2/3 is 0.66 not 0.5 and you still need to reply to above ESS issue, which has errors too. Prokaryotes (talk) 22:27, 24 September 2013 (UTC) Where on earth did you get 2/3 from? 3/2 (which the paper and the above says) is quite correctly 1.5. Are you complaining about the conversion from fractions? --Kim D. Petersen 00:19, 25 September 2013 (UTC) Ok, somehow i read 3/2 as 2/3, my bad. But the part should be made more clear. Lag effects mean ocean heat uptake. And it should be made more clear that this doesn't effect the energy coming from the sun. Prokaryotes (talk) 01:01, 25 September 2013 (UTC)

OK, so that was all confusion. If we just skip all that, can you make it clear what problems you now have? William M. Connolley (talk) 07:47, 25 September 2013 (UTC)

1. reply above, address the points i made.

2. As i wrote before, the section is not mentioning the solar cycle, the section has probs in regards to WP:JARGON, the last part needs to be updated. The part is about modelling and is not mentioning the study conclusion - that they found a 95% confidence about the solar forcing (solar max and min). What is now briefly called "lag" is known as ocean heat content uptake. Are you going to rewrite this? Do you want me to rewrite this? Prokaryotes (talk) 09:56, 25 September 2013 (UTC)

A 2013 study on this subject http://onlinelibrary.wiley.com/doi/10.1002/rog.20022/abstract Prokaryotes (talk) 14:27, 25 September 2013 (UTC)

Jargon, eh? Well, perhaps we can try to fix that. Which bits do you think are a problem. Direct quotation is probably best William M. Connolley (talk) 14:41, 25 September 2013 (UTC)

The earlier edit, the initial part (maybe use that or edit it)

Sunspots and faculae variations on the sun’s surface periodical change solar irradiance, also called the solar constant, on a roughly 11-year cycle by about 0.07%. Solar luminosity is about 0.9 W/m² brighter during solar maximum than during solar minimum.

Now, i have the most issue with this part and i don't know if this is even relevant any longer, this was based on models from 2008, which overestimated OHC uptake. Pretty sure this has been accounted for. Hence why i linked Abraham 2013 above, which might give some clues, but still do we have to include this here when explaining the solar forcing??

From this data (incorporating the Earth's albedo and the fact that the solar absorption cross-section is 1/4 of the surface area of the Earth), Tung, Zhou and Camp (2008) derive a transient sensitivity value of 0.69 to 0.97 °C/(W/m2).[41] This would correspond to a transient climate sensitivity to carbon dioxide doubling of 2.5 to 3.6 K, similar to the range of the current scientific consensus. However, they note that this is the transient response to a forcing with an 11 year cycle; due to lag effects, they estimate the equilibrium response to forcing would be about 1.5 times higher.

Prokaryotes (talk) 16:00, 25 September 2013 (UTC)

I'm still not sure which are the jargon terms you don't like, in either of your two quotes above. Perhaps you could bold the "jargon" ones you think are difficult? William M. Connolley (talk) 20:35, 25 September 2013 (UTC)

The first quote is from the edit i made, and you removed. Are you following? The second quote is to vague and to technical - (as i've pointed out above and as i've wrote in that edit note is weasel worded) This part has become irrelevant, because it refers to specific model simulations from 2008 and as pointed out to you now several times is not related to the section of solar forcing. So you either make that more clear, or you re-add my addition. Further, you continue to ignore every single question and argument i made in this entire discussion. Prokaryotes (talk) 23:48, 25 September 2013 (UTC)

The point here in relation to CS (Climate sensitivity) is TSI (Total solar irradiance). Here are more recent papers by Tung http://depts.washington.edu/amath/research/articles/Tung/journals/ Prokaryotes (talk) 07:15, 26 September 2013 (UTC)

You need to stop shouting, or otherwise find someone else to talk to. Your complaints that I'm not listening are unfounded. On the contrary, I'm listening to you, and trying to understand your problems, but every time I do that you wriggle away to something different.

I asked ("Jargon, eh? Well, perhaps we can try to fix that. Which bits do you think are a problem") in response to which I expected you to provide examples. Confusingly, the first "example" you provided was totally irrelevant, which hasn't helped. OK, we'll forget that. The second example doesn't obviously contain jargon, and I asked to to indicate which bits of it do ("Perhaps you could bold the "jargon" ones you think are difficult"). You haven't done that, instead you just say its "to [sic] vague and to [sic] technical". I don't quite understand that - are you withdrawing your complaint of jargon and substituting something different, or what? Or do you want to drop the complaint about "jargon" entirely, and talk about relevance instead? William M. Connolley (talk) 07:30, 26 September 2013 (UTC)

WP:JARGON includes WP:TECHNICAL, https://en.wikipedia.org/wiki/Wikipedia:Make_technical_articles_understandable So could you please, separate model related stuff from solar cycle forcing, which is the topic here. Prokaryotes (talk) 08:21, 26 September 2013 (UTC)

OK, perhaps you're not very interested in the "jargon" problem after all. I'll try to understand your other complaint, instead. You think that the para in your second quote "is not related to the section of solar forcing". I'm afraid I don't understand you, since C+T is clearly about solar forcing. Can you expand your complaint? William M. Connolley (talk) 20:41, 26 September 2013 (UTC)

The part is not mentioning the main conclusion of the cited study, which is the 95% confidence level about the solar forcing cycle, why is this not mentioned? Instead the above quoted part refers to model underestimation of the ocean heat uptake. However, since 2007/2008 a lot new science has been released with updated model simulations. The stuff on transient climate sensitivity TSI and transient climate response TCR should go with an updated source and content into the TCS section. OHC relates to changes in wind circulation, patterns which were recently tied to La Nina. Prokaryotes (talk) 21:00, 26 September 2013 (UTC)

References

Sensitivity to solar forcing: 1.5 times higher

Dear authors, I have a question which is (I think) not covered by the other discussion about this section: Is ECR really 1,5 times higher (which means 250% of TCR) or is it 1,5 times as high (which is what the section about ECR/TCR the IPCC AR5 report section WGI D.2 about ECR/TCR suggests? Please note e.g. that if a quantity gets 0.33 times (33%) higher, it is 1.33 as high as it was before. --129.13.156.13 (talk) 14:17, 7 October 2015 (UTC)

P.S.: I looked into the paper of Tung, Zhou and Camp. They give the values: TCR 2.5 to 3.6K, and ECS(here sensitivity, I got it wrong) 3.8 to 5.4 K. So my correction is valid. --129.13.156.13 (talk) 14:58, 7 October 2015 (UTC)

You might want to read the more recent papers and IPCC reports referenced in the article. There are usually good reviews of the literature. 2007 is pretty old in this field. Also, don't expect that kind of numerical precision you are looking for. Climate sensitivity is one of the major open questions in the field, the most recent IPCC AR5 of 1.5C to 4.5C, i.e., over factor of 3 is really an agreement to disagree, and they refused to give a best estimate. "No best estimate for equilibrium climate sensitivity can now be given because of a lack of agreement on values across assessed lines of evidence and studies” (SPM-11, fn 16)" The Knutti and Hegerl paper is good at explaining that the climate sensitivity is different for different forcings which couple to the climate differently in vertical and spatial distribution.Poodleboy (talk) 01:46, 15 July 2016 (UTC)